I run GAS boats but I have an EP Racing boat that I use for boat retrevials. I buy these boats off Ebay for a song , they have great value for retrevials. I've bolted an outrigger to the deck that hangs off the back of the boat. A fishing line is attached to that. When a boat is stalled in the middle of the lake, this guy go'es to work. The boat comes stock with an 1800ma, 7.2v NI CAD battery. Some days I do a lot of retrevials and the battery won't hold up. I have since switched over to 3000ma 7.2v NIMH battery from Tower Hobbies.
I have a Piranha peak charger from Tower that I've been using to charge before I go to the lake. I have the charger set at 7v, with a 3amp charge rate. After a couple months, the battery is toast![:@] Am I using too high a charge rate? I was at a battery demonstration a while back and the guy said you can charge NIMH's at 1amp/1000ma. Is this too much? Why am I frying batteries?? Thanks, Brian

first problem nicad at least use nimh and if you charge it a couple times a day thats to much if i remember right it,s like twice a day at most just get a cheap lipo battery and a cheap charger and cherge less cause the cells last longer and they can be charged as soon as there cool

Thanks for the reply Animalnut. I AM running a NIMH battery pac, and I am only charging it once before I leave home to go to the lake. The first NIMH I had lasted over a year. Now I'm frying em after about about 3 months use once a weekend. Brian

There are several potential problems.

First, most NiMH cells should NEVER be run below 0.9 volts per cell. This would mean that the boat comes in with a visibly lower speed than when the charge was full. If this happens very often, the pack will be permanently damaged.

Second, the cells should not be stored discharged, they should be stored charged. If they drop too much when in storage, the pack will be permanently damaged.

Third, the pack should be balanced periodically. This means charging them at 0.5 amps for over 12 hours. This puts the maximum charge in every cell and helps keep the pack lasting longer.

Fourth, the packs are cheap junk to begin with and just are not intended to last long. This is a problem with some of the cheap sport packs sold at RadioShakk, etc. - most people who buy them want the lowest possible cost, and only run their toys a few times anyway. Better quality cells will last a lot longer if cared for as in the above three cases.


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Thanks Fluid, I don't run the pac down to nothing, never have. A lot of times the boat will not even get used (my boats don't break down! LOL) altho the battery pac has been charged at home before I go to the lake. I've got a new pac comming, I wouldn't exactly call them cheap @ $25.00 + shipping! http://www3.towerhobbies.com/cgi-bin...?&I=LH2168&P=1 Guess I'm not battery smart. I think I'll see how low I can set the amps on the Pirahna charger for the initial charge. Then I'll crank the amps up a bit for future charges. Thanks, Brian

how fast do u run the boat when retriving? you could be over heating the batterys and putting stress on the motors.most retrival boats are those toys r us boats. they work good as well. i have used my same retrival boat for 3-5 years. [link=http://www.toysrus.com/product/index.jsp?productId=2332031]this is my retrival boat[/link]

Maxx, These boats have dual 380 motors. There is no variable speed, it's full blast or off. When doing a retrevial you drive the boat out around behind the stalled boat, stop the boat, then reel both boats in. I use a 10" steel leader on the fishing line. That hooks into the rudder when pulling the boats back. Don't really see where the motors would get hot, I'm running the same voltage that the boat came with. I've been using this setup for 4 years now. I call these boats, "throw aways"! If you let them sit out in the sun, the cheap plastic will get brittle, cracks and leaks form after that. Time for a new one! LOL Brian

by towing the boat you can put a load on the eltric motors and they willover work themselves and over heat the battery . its happend b4

this is what happens to a battery with a over load on the motor.

Maxx, Look at the pic up top. I'm not towing anything. Drive the retrevial boat out - make a half circle around the stalled boat - turn radio off - reel both boats in - done deal! Brian

I agree with fluid. 1/10C to equalize voltage across all cells, and store charged. Also, batteries don't know if it's yesterday, today or tomorrow, you can charge them as many times as you want in a day.

Ryan